Experimental demonstration of OAM-based transmitter mode diversity data transmission under atmosphere turbulence

• Published in: Optics express 2021-04, Vol.29 (9), p.13171-13182
• Main Authors: Wang, Andong, Zhu, Long, Deng, Mingliang, Lu, Bing, Guo, Xiaojin
• Format: Article
• Language: English
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.420193

Twisted light carrying orbital angular momentum (OAM), which features helical phase front, has shown its potential applications in diverse areas, especially in optical communications. For OAM-based free-space optical (FSO) links, a significant challenge is the power fading induced by atmospheric turbulence. In this paper, we experimentally demonstrate the mitigation of atmospheric turbulence effects with an OAM-based transmitter mode diversity scheme. By designing multi-OAM phase patterns, we successfully generate multiple OAM modes (OAM , OAM , OAM ) carrying the same data stream for transmitter diversity without adding system complexity. An intensity-modulated direct-detection (IM-DD) system with 39.06 Gbit/s discrete multi-tone (DMT) signal is employed to confirm the feasibility of the OAM-based transmitter mode diversity scheme under atmosphere turbulence. The obtained experimental results show that the received power fluctuation and average bit-error rate (BER) are decreased under moderate to strong turbulence compared to the traditional single OAM mode transmission. In addition, the required transmitted power at 10% interruption probability is relaxed by nearly 2 dB under moderate to strong turbulence.